The lengths of lumber a machine cuts are normally distributed with a mean of 90 inches and a standard deviation of 0.3 inch.(a) What is the probability that a randomly selected board cut by the machine has a length greater than 90.07 inches?(b) A sample of 42 boards is randomly selected. What is the probability that their mean length is greater than 90.07 inches?.....(a) The probability is 0.4078 .(Round to four decimal places as needed.)(b) The probability is(Round to four decimal places as needed.)

GivenMean(μ)=90standard deviation(σ)=0.3

Answered: The lengths of lumber a machine cuts…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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